Piston



HENRY VOGT, OF LOUISVILLE, KENTUCKY, ASSIGNOR TO THE SULZER-VOGT MACHINE COMPANY, OF KENTUCKY.

PISTON.

SPECIFICATION forming part of Letters Patent No. 546,441, dated September 1'7, 1895.

Application filed November 22, 1894. Serial No. 529,580. (No model.)

To all whom it may concern/.-

Be it known that I, HENRY VOGT, a citizen of the United States, residing at Louisville, in the county of Jederson and State of Kentucky, have invented certain new and useful Improvements in Pistons, of which the following is a full, clear, and exact description.

This invention relates to pistons especially adaptable in the cylinders of pumps or engines used in ice-making wherein certain fluids or gases are to be acted upon.

In the operation of pumps used in forcing fluids in the process of making artificial ice it is desirable that the piston at each stroke shall almost, if not quite, touch the cylinderhead, so that no gas shall be left in the cylinder; but ordinarily pistons and cylinders cannot be made to operate with such extreme accuracy, because the slightest variation in stroke, due to the wearing away of parts or the presence of a foreign body in the cylinder, such as a broken valve, would cause the piston to strike a blow upon the piston-head which would do injury.

My invention is designed to produce a piston which will operate with the great accuracy mentioned, but which, in case a blow is struck under the conditions mentioned, will automatically adjust itself to` save the parts from injury.

My invention consists of a collapsible piston made in two parts telescoping each other and held apart by a suitable arrangement of springs.

The invention will be described in detail with reference to the accompanying drawings, in which- Figure l is a longitudinal section of the cylinder and piston, and Fig. 2 is a transverse section of the same.

A represents the cylinder, the ports of which are omitted.

B represents the piston. It is formed of two cup-shaped parts b and b', respectively, placed with their concave sides toward each other and having an external cylindrical surface fitting the bore of the cylinder. The

part h has a rim h2, of less diameter than the main portion of the head, over which passes the edges of the head b', thus forming a telescopic connection between the two parts.

Between the two heads and inthe chamber formed thereby are arranged a series of spiral springs c. These are located in a cylindrical plane concentric with the axis of the piston.

They are mounted at each end upon short nibs c. The piston-rod, which is represented by D, passes freely through the center of both of the heads h and b". The end of the pistonrod, is capped by a nut d, resting against the 6o edge l?, and a shoulder d' is formed upon the rod against which the head b abuts. The springs are inserted under tension tending to separate the two heads equal to or exceeding the greatest fluid-pressure which will be used in the cylinder. The springs will therefore tend normally to hold the two heads of the piston against the nut and shoulder cl and ol under all working conditions and preventing collapsing of the pistou. piston will be provided externally with an annular groove, in which will be placed the packing-rings e and e.

In the operation the pistou will normally retain its full size-that is, with its two heads 7 5 against their abutments, as described. New in case a valve or other portion of the apparatus becomes broken and a piece should fall into the cylinder the stroke of the piston would be interrupted by the obstruction and 8o in driving against the head of the cylinder will cause the piston to collapse, the head b sliding over the head b and the springs becoming compressed. This action will take place whether the obstruction occurs at either side of the piston, and the invention is applicable to either single or double acting cylinders.

As a substitute for the series of spiral springs, a single large spiral spring is obvious. 9o This would be inserted concentrically with the piston-rod and occupy the same space between the heads as the series of springs described.

Having thus described my invention, I claiml. The combination with a cylinder, of a piston constructed in two parts, both fitting the bore of the cylinder, and a spring interposed between the parts, for the purpose set forth. roo

2. The combination of a cylinder and piston, and a pistou rod, the piston constructed Each head of the 7o their cavities opposite each other and with their edges overlapping to form a telescopio I;

connection, and a spring or springs located inside of the piston and tending to separate the said cup-shaped parts, substantially as described.

In testimony whereof I subscribe my signazo ture in presence of two witnesses.

HENRY voor.

Witnesses:

ROBERT WTLsoN, ALBERT E. SCOTT. 

